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1.
J Chromatogr A ; 1721: 464854, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38579528

RESUMO

Developing adsorbents with high performance and long service life for effective extracting the trace organochlorine pesticides (OCPs) from real water is attracting numerous attentions. Herein, a self-standing covalent organic framework (COF-TpPa) membrane with fiber morphology was successfully synthesized by using electrospun nanofiber membranes as template and employed as solid-phase microextraction (SPME) coating for ultra-high sensitivity extraction and analysis of trace OCPs in water. The as-synthesized COF-TpPa membrane exhibited a high specific surface area (800.83 m2 g-1), stable nanofibrous structure, and excellent chemical and thermal stability. Based on the COF-TpPa membrane, a new SPME analytical method in conjunction with gas chromatography-mass spectrometry (GC-MS) was established. This proposed method possessed favorable linearity in concentration of 0.05-2000 ng L-1, high sensitivity with enrichment factors ranging from 2175 to 5846, low limits of detection (0.001-0.150 ng L-1), satisfactory precision (RSD < 10 %), and excellent repeatability (>150 cycles), which was better than most of the reported works. Additionally, the density functional theory (DFT) calculations and XPS results demonstrated that the outstanding enrichment performance of the COF-TpPa membrane was owing to synergistic effect of π-π stacking effects, high specific surface area and hydrogen bonding. This work will expect to extend the applications of COF membrane to captures trace organic pollutants in complex environmental water, as well as offer a multiscale interpretation for the design of effective adsorbents.


Assuntos
Hidrocarbonetos Clorados , Estruturas Metalorgânicas , Nanofibras , Praguicidas , Poluentes Químicos da Água , Água , Porosidade , Poluentes Químicos da Água/análise , Microextração em Fase Sólida/métodos , Praguicidas/análise , Hidrocarbonetos Clorados/análise
2.
Mikrochim Acta ; 191(5): 276, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644435

RESUMO

Solid-phase microextraction (SPME) coupled with electrospray ionization mass spectrometry (ESI-MS) was developed for rapid and sensitive determination of endogenous androgens. The SPME probe is coated with covalent organic frameworks (COFs) synthesized by reacting 1,3,5-tri(4-aminophenyl)benzene (TPB) with 2,5-dioctyloxybenzaldehyde (C8PDA). This COFs-SPME probe offers several advantages, including enhanced extraction efficiency and stability. The analytical method exhibited wide linearity (0.1-100.0 µg L-1), low limits of detection (0.03-0.07 µg L-1), high enrichment factors (37-154), and satisfactory relative standard deviations (RSDs) for both within one probe (4.0-14.8%) and between different probes (3.4-12.7%). These remarkable performance characteristics highlight the reliability and precision of the COFs-SPME-ESI-MS method. The developed method was successfully applied to detect five kinds of endogenous androgens in female serum samples, indicating that the developed analytical method has great potential for application in preliminary clinical diagnosis.


Assuntos
Androgênios , Limite de Detecção , Microextração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Microextração em Fase Sólida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Androgênios/sangue , Androgênios/análise , Androgênios/química , Feminino , Estruturas Metalorgânicas/química , Reprodutibilidade dos Testes
3.
Sci Total Environ ; 927: 172227, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582104

RESUMO

The sensory quality of drinking water, and particularly its taste and odor (T&O) is a key determinant of consumer acceptability, as consumers evaluate water by their senses. Some of the conventional treatment processes to control compounds which impart unpleasant T&O have limitations because of their low efficiency and/or high costs. Therefore, there is a great need to develop an effective process for removing T&O compounds without secondary concerns. The primary objective of this study was to assess for the first time the effectiveness of spirulina-based carbon materials in removing geosmin (GSM) and 2-methylisoborneol (2-MIB) from water, two commonly occurring natural T&O compounds. The efficiency of the materials to remove environmentally relevant concentrations of GSM and 2-MIB (ng L-1) from ultrapure and raw water was investigated using a sensitive headspace solid-phase microextraction coupled with gas chromatography mass spectrometry (HS-SPME-GC/MS) method. Moreover, the genotoxic and cytotoxic effects of the spirulina-based materials were assessed for the first time to evaluate their safety and their potential in the treatment of water for human consumption. Based on the results, spirulina-based materials were found to be promising for drinking water treatment applications, as they did not exert geno-cytotoxic effects on human cells, while presenting high efficiency in removing GSM and 2-MIB from water.


Assuntos
Água Potável , Odorantes , Spirulina , Paladar , Poluentes Químicos da Água , Purificação da Água , Água Potável/química , Odorantes/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Naftóis , Humanos , Canfanos , Adsorção , Microextração em Fase Sólida/métodos , Carbono , Cromatografia Gasosa-Espectrometria de Massas
4.
Methods Mol Biol ; 2788: 39-48, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656507

RESUMO

Plant volatile organic compounds (VOCs) are organic chemicals that plants release as part of their natural biological processes. Various plant tissues produce VOCs, including leaves, stems, flowers, and roots. VOCs are essential in plant communication, defense against pests and pathogens, aroma and flavor, and attracting pollinators. The study of plant volatiles has become an increasingly important area of research in recent years, as scientists have recognized these compounds' important roles in plant physiology. As a result, there has been a growing interest in developing methods for collecting and analyzing plant VOCs. HS-SPME-GC-MS (headspace solid-phase microextraction-gas chromatography-mass spectrometry) is commonly used for plant volatile analysis due to its high sensitivity and selectivity. This chapter describes an efficient method for extracting and identifying volatile compounds by HS-SPME coupled with GC-MS in tomato fruits.


Assuntos
Frutas , Cromatografia Gasosa-Espectrometria de Massas , Solanum lycopersicum , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Solanum lycopersicum/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Microextração em Fase Sólida/métodos , Frutas/química
5.
Anal Chim Acta ; 1304: 342555, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637039

RESUMO

BACKGROUND: Omics is used as an analytical tool to investigate wine authenticity issues. Aging authentication ensures that the wine has undergone the necessary maturation and developed its desired organoleptic characteristics. Considering that aged wines constitute valuable commodities, the development of advanced omics techniques that guarantee aging authenticity and prevent fraud is essential. RESULTS: Α solid phase microextraction Arrow method combined with comprehensive two-dimensional gas chromatography-mass spectrometry was developed to identify volatiles in red wines and investigate how aging affects their volatile fingerprint. The method was optimized by examining the critical parameters that affect the solid phase microextraction Arrow extraction (stirring rate, extraction time) process. Under optimized conditions, extraction took place within 45 min under stirring at 1000 rpm. In all, 24 monovarietal red wine samples belonging to the Xinomavro variety from Naoussa (Imathia regional unit of Macedonia, Greece) produced during four different vintage years (1998, 2005, 2008 and 2015) were analyzed. Overall, 237 volatile compounds were tentatively identified and were treated with chemometric tools. Four major groups, one for each vintage year were revealed using the Hierarchical Clustering Analysis. The first two Principal Components of Principal Component Analysis explained 86.1% of the total variance, showing appropriate grouping of the wine samples produced in the same crop year. A two-way orthogonal partial least square - discriminant analysis model was developed and successfully classified all the samples to the proper class according to the vintage age, establishing 17 volatile markers as the most important features responsible for the classification, with an explained total variance of 88.5%. The developed prediction model was validated and the analyzed samples were classified with 100% accuracy according to the vintage age, based on their volatile fingerprint. SIGNIFICANCE: The developed methodology in combination with chemometric techniques allows to trace back and confirm the vintage year, and is proposed as a novel authenticity tool which opens completely new and hitherto unexplored possibilities for wine authenticity testing and confirmation.


Assuntos
Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Quimiometria , Análise por Conglomerados , Compostos Orgânicos Voláteis/análise
6.
Anal Chem ; 96(11): 4639-4646, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501258

RESUMO

Multicomponent reactions offer efficient and environmentally friendly strategies for preparing monoliths suitable for applications in analytical chemistry. In the described study, a multicomponent reaction was utilized for the one-pot miniaturized preparation of a poly(propargyl amine) polymer inside commercial silica-lined PEEK tubing. The reaction involved only small amounts of reagents and was characterized by atom economy. The resulting monolithic column was incorporated into an autosampler system for the online extraction and cleanup of ß-estradiol from human serum. Sample pretreatment was simplified to a simple dilution with methanol and centrifugation to remove proteins. The resulting platform included LC-MS analysis in multiple reaction monitoring for quantitative analysis of ß-estradiol. The method was validated in serum, demonstrating practical applicability for the monitoring of fertile women. Recoveries were above 94%, and LOD and LOQ values at 0.008 and 0.18 ng mL-1, respectively. The developed platform proved to be competitive with previous methods for solid-phase microextraction of ß-estradiol in serum, with comparable recovery and sensitivity but with the advantage of nearly complete automation. The environmental impact of the process was evaluated as acceptable due to the miniaturization of the monolith synthesis and the automation of extraction. The drawback associated with the LC-MS technique can be reduced by the inclusion of additional analytes in a single investigation. The work demonstrates that multicomponent reactions are versatile, economical, and possibly a green methodology for producing reversed-phase and mixed-mode sorbents, enabling miniaturization of the entire analytical procedure from the preparation of extraction sorbents to analysis.


Assuntos
60705 , Espectrometria de Massas em Tandem , Humanos , Feminino , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Estradiol , Microextração em Fase Sólida/métodos , Extração em Fase Sólida/métodos
7.
Anal Chim Acta ; 1301: 342468, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38553125

RESUMO

BACKGROUND: Acetone, isoprene, and other volatile organic compounds (VOCs) in exhaled breath have been shown to be biomarkers for many medical conditions. Researchers use different techniques for VOC detection, including solid phase microextraction (SPME), to preconcentrate volatile analytes prior to instrumental analysis by gas chromatography-mass spectrometry (GC-MS). These techniques include a previously developed method to detect VOCs in breath directly using SPME, but it is uncommon for studies to quantify exhaled volatiles because it can be time consuming due to the need of many external/internal standards, and there is no standardized or widely accepted method. The objective of this study was to develop an accessible method to quantify acetone and isoprene in breath by SPME GC-MS. RESULTS: A system was developed to mimic human exhalation and expose VOCs to a SPME fiber in the gas phase at known concentrations. VOCs were bubbled/diluted with dry air at a fixed flow rate, duration, and volume that was comparable to a previously developed breath sampling method. Identification of acetone and isoprene through GC-MS was verified using standards and observing overlaps in chromatographic retention/mass spectral fragmentation. Calibration curves were developed for these two analytes, which showed a high degree of linear correlation. Acetone and isoprene displayed limits of detection/quantification equal to 12 ppb/37 ppb and 73 ppb/222 ppb respectively. Quantification results in healthy breath samples (n = 15) showed acetone concentrations spanned between 71 ppb and 294 ppb, and isoprene varied between 170 ppb and 990 ppb. Both concentration ranges for acetone and isoprene in this study overlap with those reported in existing literature. SIGNIFICANCE: Results indicate the development of a system to quantify acetone and isoprene in breath that can be adapted to diverse sampling methods and instrumental analyses beyond SPME GC-MS.


Assuntos
Butadienos , Hemiterpenos , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Acetona/análise , Expiração , Testes Respiratórios/métodos , Compostos Orgânicos Voláteis/análise
8.
Food Chem ; 446: 138871, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38432133

RESUMO

A new graft copolymer composed of polystyrene and polylinoleic acid (PLinas) with the sodium salt of iminodiacetate (Ida) was synthesized and used as an adsorbent. The vortex-assisted dispersive solid-phase micro-extraction (VA-dSPµE) method was used for the extraction and pre-concentration of chromium. Multivariate methodologies, such as factorial design and 3D surface plots, were applied for screening and optimizing effective extraction parameters. The influence of diverse analytical parameters, such as pH, sample volume, and interfering ions, on the extraction of chromium was studied. The calibration standard curve exhibited a linear range from 0.01 to 0.50 µg L-1. The relative standard deviation and limit of detection were found to be 1.65 % and 0.003 µg L-1, respectively. Extraction recoveries were found in the range of 96 to 99 % by using certified reference materials (CRMs). The adsorbent capacity of PLinas-Ida was found to be 112 mg g-1. The VA-dSPµE method demonstrated its effectiveness in the pre-concentration and determination of chromium within samples of foodstuffs by graphite furnace-atomic absorption spectrometry (GF-AAS).


Assuntos
Cromo , Extração em Fase Sólida , Extração em Fase Sólida/métodos , Polímeros/química , Microextração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos
9.
Food Chem ; 447: 139023, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38507949

RESUMO

This study presents a method employing gas chromatography coupled with mass spectrometry and headspace solid-phase microextraction (HS-SPME-GC-MS), supplemented with chemometrics (Soft independent modelling of class analogies - SIMCA), to analyze volatile organic compound (VOCs) profiles in suspect whiskey samples. Furthermore, a sensory analysis of aroma and color was conducted with a panel of 52 non-trained volunteers to evaluate their ability to discriminate and preference for counterfeit whiskeys. The HS-SPME-GC-MS method successfully distinguished 41 seized samples from authentic beverages. Interestingly, sensory analysis revealed that panelists could differentiate between counterfeit and authentic samples with a reference standard but did not consistently show a preference for aroma. In some cases, there was even a preference for the color of counterfeit whiskeys. The findings suggest that sensorial tests alone may not effectively distinguish counterfeit from authentic whiskeys, especially for non-expert consumers, highlighting the need for analytical instrumentation methods in fraud detection.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Humanos , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Bebidas Alcoólicas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas , Microextração em Fase Sólida/métodos
10.
Anal Chem ; 96(14): 5363-5367, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38535996

RESUMO

Proteomics of human saliva samples was achieved for the first time via biocompatible solid-phase microextraction (bio-SPME) devices. Upon introduction of a porogen to a conventional C18 coating, porous C18/polyacrylonitrile (PAN) SPME blades were able to extract peptides up to 3.0 kDa and more peptides than commercial SPME blades. Following Trypsin digestion, salivary proteomic analysis was achieved via SPME-LC-MS/MS. Seven endogenous proteins were consistently identified in all saliva samples via bio-SPME. Taking advantage of this strategy, untargeted peptidomics was applied for the comparison of saliva samples between healthy and SARS-CoV-2 positive individuals. The results showed clear peptidomic differences between the viral and healthy saliva samples. This proof-of-concept study demonstrates the potential of bio-SPME-LC-MS/MS for peptidomics and proteomics in biomedical applications.


Assuntos
60705 , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Microextração em Fase Sólida/métodos , Saliva/química , Proteômica , Peptídeos/análise
11.
J Chromatogr A ; 1720: 464775, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38452559

RESUMO

The contents of target substances in biological samples are usually at low concentration levels, and the matrix of biological samples is usually complex. Sample preparation is considered a very critical step in bioanalysis. At present, the utilization of microextraction sampling technology has gained considerable prevalence in the realm of biological analysis. The key developments in this field focus on the efficient microextraction media and the miniaturization and automation of adaptable sample preparation methods currently. In this review, the recent progress on the microextraction sampling technologies for bioanalysis has been introduced from point of view of the preparation of microextraction media and the microextraction sampling strategies. The advance on the microextraction media was reviewed in detail, mainly including the aptamer-functionalized materials, molecularly imprinted polymers, carbon-based materials, metal-organic frameworks, covalent organic frameworks, etc. The advance on the microextraction sampling technologies was summarized mainly based on in-vivo sampling, in-vitro sampling and microdialysis technologies. Moreover, the current challenges and perspective on the future trends of microextraction sampling technologies for bioanalysis were briefly discussed.


Assuntos
Microextração em Fase Sólida , Manejo de Espécimes , Microextração em Fase Sólida/métodos , Tecnologia , Polímeros Molecularmente Impressos , Automação
12.
J Pharm Biomed Anal ; 243: 116074, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38437785

RESUMO

Rapid diagnosis of diseases is one of the challenging areas in clinical research. From the analytical chemist's perspective, the main challenges are isolating the compounds from the bio-specimen and lengthy analysis times. In this regard, solid phase microextraction offers a platform to address the abovementioned challenges. Moreover, its sharp tip-thin film geometry, known as coated blade spray (CBS), can enhance the extraction and act as an ionization source in direct mass spectrometric analysis. In this study, a new CBS device specifically designed for polar analytes was prepared and optimized to determine urinary metabolites. For this purpose, polyacrylonitrile (PAN) was selected as a base polymer as it can be electrospun to form a nanofibrous structure, and it can be modified with weak ion exchange moieties to interact with polar analytes. Following the electrospinning of PAN, hydrolysis was optimized, and conditions leading to sufficient extraction enhancement without dissolving the polymer were obtained when probes were treated with 5.0 M of NaOH for 2.5 h. Using the coated blades prepared as explained, the evaluation of various extraction conditions showed that 5 min is sufficient for equilibrium extraction. In addition, the solution's ionic strength and pH significantly affect the extraction. Optimum sorption was obtained at no salt added and pH 7.0 conditions. The CBS-MS optimization showed that 10.0 µL of ACN/MeOH/H2O (40:40:20, v/v/v) with formic acid kept for 15 seconds on the blade before voltage application leads to the highest signal. The limits of quantification of the analytes are between 50 and 100 ng/mL.


Assuntos
Microextração em Fase Sólida , Espectrometria de Massas , Microextração em Fase Sólida/métodos
13.
J Breath Res ; 18(2)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38467063

RESUMO

Volatilomics is a powerful tool capable of providing novel biomarkers for the diagnosis of gastric cancer. The main objective of this study was to characterize the volatilomic signatures of gastric juice in order to identify potential alterations induced by gastric cancer. Gas chromatography with mass spectrometric detection, coupled with headspace solid phase microextraction as the pre-concentration technique, was used to identify volatile organic compounds (VOCs) released by gastric juice samples collected from 78 gastric cancer patients and two cohorts of controls (80 and 96 subjects) from four different locations (Latvia, Ukraine, Brazil, and Colombia). 1440 distinct compounds were identified in samples obtained from patients and 1422 in samples provided by controls. However, only 6% of the VOCs exhibited an incidence higher than 20%. Amongst the volatiles emitted, 18 showed differences in their headspace concentrations above gastric juice of cancer patients and controls. Ten of these (1-propanol, 2,3-butanedione, 2-pentanone, benzeneacetaldehyde, 3-methylbutanal, butylated hydroxytoluene, 2-pentyl-furan, 2-ethylhexanal, 2-methylpropanal and phenol) appeared at significantly higher levels in the headspace of the gastric juice samples obtained from patients; whereas, eight species showed lower abundance in patients than found in controls. Given that the difference in the volatilomic signatures can be explained by cancer-related changes in the activity of certain enzymes or pathways, the former set can be considered potential biomarkers for gastric cancer, which may assist in developing non-invasive breath tests for the diagnosis of this disease. Further studies are required to elucidate further the mechanisms that underlie the changes in the volatilomic profile as a result of gastric cancer.


Assuntos
Neoplasias Gástricas , Compostos Orgânicos Voláteis , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testes Respiratórios/métodos , Biomarcadores/análise , Compostos Orgânicos Voláteis/análise , Microextração em Fase Sólida/métodos , Suco Gástrico/metabolismo
14.
J Chromatogr A ; 1720: 464813, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38490142

RESUMO

Estrogens and bisphenols are typical endocrine disruptors (EDs) that pose a potential hazard to the human body due to their widespread presence in aqueous environments. In this study, a ß-cyclodextrin porous crosslinked polymer (ß-CD-PCP) was prepared in-situ on a glass fiber surface by a nucleophilic substitution reaction. An effective and sensitive solid phase microextraction method using functionalized glass fiber with ß-CD-PCP coating as the adsorbent was established for the detection of 11 EDs in a water environment. The ß-CD-PCP was in-situ prepared on a glass fiber surface by a nucleophilic substitution reaction. The ß-CD-PCP successfully separated five estrogens (ESTs) and six bisphenols (BPs) through hydrophobic and π-π interactions. The conditions affecting extraction were optimized. Under the optimized conditions, the ESTs obtained a high enrichment effect (1795-2328), low limits of detection (0.047 µg L-1) and a good linearity range (0.2-15.0 µg L-1). Furthermore, the spiked recoveries of analyte ESTs in aqueous environments were between 82.9-115.7 %. The results indicated that the prepared functionalized glass fibers exhibited good adsorption properties, and the established analytical method was reliable for monitoring trace ESTs and BPs in aqueous environments.


Assuntos
Disruptores Endócrinos , Vidro , Humanos , Disruptores Endócrinos/análise , Água/química , Microextração em Fase Sólida/métodos , Estrogênios/análise
15.
Sci Total Environ ; 925: 171726, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492591

RESUMO

Polycyclic aromatic hydrocarbons (PAHs), a group of seriously hazardous environmental contaminants, have attracted extensive attention due to their carcinogenicity, genotoxicity, mutagenicity, and ubiquity. In this work, the excellent hydrophobic trifluoromethyl-enriched covalent organic framework (CF3-COF) was designed and synthesized as coating of solid-phase microextraction (SPME). The CF3-COF offered a high adsorption selectivity for PAHs, which could be attributed to the multiple interactions between the CF3-COF and PAHs, including hydrophobicity interaction, π-π and H bond interactions. Furthermore, headspace (HS) and direct immersion (DI) dual-mode solid-phase microextraction (HS/DI-SPME) were innovatively integrated as a dual-mode extraction by varying the length of SPME coating on stainless-steel, which could simultaneously and efficiently extract 16 PAHs with different volatile. Amazingly, the proposed strategy achieved fast adsorption for PAHs and shortened the adsorption equilibrium time to 15 min. By further integrating with gas chromatography tandem mass spectrometry (GC-MS/MS), PAHs could be detected in the range of 0.008-0.16 ng mL-1 with a quantitative limit of 0.029-0.47 ng mL-1, respectively. The recoveries of PAHs in water samples ranged from 80.84 to 117.67 %. This work indicates that the dual-mode CF3-COF-SPME is a promising candidate for the enrichment of multiple hazardous substances in complicated samples.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem , Cromatografia Gasosa-Espectrometria de Massas , Poluentes Químicos da Água/análise , Limite de Detecção , Interações Hidrofóbicas e Hidrofílicas , Água/química
16.
Sci Rep ; 14(1): 6870, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519512

RESUMO

Bee bread is one of the least studied bee products. In this study, ten bee bread samples were characterized using palynology and HS-SPME-GC-MS (headspace solid-phase microextraction gas chromatography-mass spectrometry). In total, over one hundred different volatile components were identified, belonging to different chemical groups. Only ten common components were detected in all the samples. These volatiles were ethanol, ethylene chloride, ethyl acetate, acetic acid, α-pinene, furfural, nonane, nonanal, n-hexane and isovaleric acid. Several other components were commonly shared among various bee bread samples. Over sixty detected compounds have not been previously reported in bee bread. The analysis required a mild extraction temperature of 40 °C, as higher temperatures resulted in the Maillard reaction, leading to the production of furfural. The profile of volatile compounds of the tested bee pollen samples was complex and varied. Some relationships have been shown between botanical origin and volatile organic compound profile.


Assuntos
Própole , Compostos Orgânicos Voláteis , Abelhas , Animais , Furaldeído/análise , Compostos Orgânicos Voláteis/análise , Ácido Acético , Microextração em Fase Sólida/métodos
17.
Talanta ; 273: 125816, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442561

RESUMO

The refinement and optimization of a method combining headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) was successfully performed for the first time to determine seven carbonyl and dicarbonyl compounds, including glyoxal, methylglyoxal, dimethylglyoxal, and malondialdehyde in infant formulae, related to lipid peroxidation. HS-SPME was utilized for simultaneous extraction and derivatization with pentafluorophenylhydrazine (PFPH). Critical parameters such as temperature, pH, extractive phase, and salting-out were meticulously investigated and fine-tuned by an asymmetrical 2232//9 screening design to ensure the method's efficacy and reliability. Optimal conditions included a PFPH concentration of 5 g/L, pH 5.0, head-space extraction at 60 °C within 10 min, utilizing a DVB/CAR/PDMS coating, and a 20% w/w salting-out. The analytical validation of this method, compliant with FDA guidelines, demonstrated exceptional linearity, sensitivity, specificity, precision (RSD ≤13.8%), and accuracy (84.8% ≤ recovery ≤111.5%). The metric approach AGREEprep confirms its eco-friendliness, marking a significant step towards an environmentally conscious approach in infant formula analysis. An occurrence study conducted on 25 infant formula samples revealed widespread carbonyl and dicarbonyl compounds in both powdered and liquid variants. ANOVA results exhibited variations in compound concentrations among different sample groups. Clustering analyses delineated distinct groups based on carbonyl content, indicating the potential of these compounds as markers for lipid peroxidation and food quality assessment. This method serves as a valuable tool for evaluating infant formula quality, stability towards oxidation, and safety.


Assuntos
Fluorbenzenos , Fluorocarbonos , Hidrazinas , Fórmulas Infantis , Microextração em Fase Sólida , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Peroxidação de Lipídeos , Reprodutibilidade dos Testes , Compostos Orgânicos
18.
Molecules ; 29(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474653

RESUMO

Matteuccia struthiopteris is one of the most globally consumed edible ferns and widely used in folk medicine. Reports mainly focus on young fronds and the rhizome which are common edible medicinal parts. However, there are few detailed reports on other parts. Therefore, the volatile components of different parts based on HS-SPME-GC-MS were identified, and total flavonoid contents, antioxidant activities and acetylcholinesterase inhibitory activities were compared in order to reveal the difference of volatile components and potential medicinal value of different parts. The results showed that total flavonoid contents, antioxidant activities and volatile components of different parts were obviously different. The crozier exhibited the strongest antioxidant activities, but only underground parts exhibited a dose-dependent inhibition potential against AChE. Common volatile compounds were furfural and 2-furancarboxaldehyde, 5-methyl-. In addition, it was found that some volatile components from adventitious root, trophophyll, sporophyll and petiole were important ingredients in food, cosmetics, industrial manufacturing and pharmaceutical applications.


Assuntos
Acetilcolinesterase , Antioxidantes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Flavonoides , Microextração em Fase Sólida/métodos
19.
Sci Rep ; 14(1): 5752, 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459176

RESUMO

Herbal spices are widely consumed as food additives owing to their distinct aroma and taste as well as a myriad of economic and health value. The aroma profile of four major spices including bay leaf, black pepper, capsicum, and fennel was tested using HS-SPME/GC-MS and in response to the most widely used spices´ processing methods including autoclaving and γ-radiation at low and high doses. Additionally, the impact of processing on microbial contamination of spices was tested using total aerobic count. GC-MS analysis led to the identification of 22 volatiles in bay leaf, 34 in black pepper, 23 in capsicum, and 24 in fennel. All the identified volatiles belonged to oxides/phenols/ethers, esters, ketones, alcohols, sesquiterpene and monoterpene hydrocarbons. Oxides/phenol/ethers were detected at high levels in all tested spices at ca. 44, 28.2, 48.8, 61.1%, in bay leaves, black pepper, capsicum, and fennel, respectively of the total blend and signifying their typical use as spices. Total oxides/phenol/ethers showed an increase in bay leaf upon exposure to γ-radiation from 44 to 47.5%, while monoterpene hydrocarbons were enriched in black pepper upon autoclaving from 11.4 in control to reach 65.9 and 82.6% for high dose and low dose of autoclaving, respectively. Cineole was detected in bay leaf at 17.9% and upon exposure to autoclaving at high dose and γ-radiation (both doses) its level increased by 29-31%. Both autoclaving and γ-radiation distinctly affected aroma profiles in examined spices. Further, volatile variations in response to processing were assessed using multivariate data analysis (MVA) revealing distinct separation between autoclaved and γ-radiated samples compared to control. Both autoclaving at 115 °C for 15 min and radiation at 10 kGy eliminated detected bioburden in all tested spices i.e., reduced the microbial counts below the detection limit (< 10 cfu/g).


Assuntos
Foeniculum , Piper nigrum , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Fenol/análise , Microextração em Fase Sólida/métodos , Quimiometria , Especiarias , Monoterpenos/análise , Éteres , Óxidos , Compostos Orgânicos Voláteis/análise
20.
J Am Soc Mass Spectrom ; 35(3): 421-432, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38326105

RESUMO

Skin volatile emissions offer a noninvasive insight into metabolic activity within the body as well as the skin microbiome and specific volatile compounds have been shown to correlate with age, albeit only in a few small studies. Building on this, here skin volatiles were collected and analyzed in a healthy participant study (n = 60) using a robust headspace-solid phase microextraction (HS-SPME) gas chromatography-mass spectrometry (GC-MS) workflow. Following processing, 18 identified compounds were deemed suitable for this study. These were classified according to gender influences and their correlations with age were investigated. Finally, 6 volatiles (of both endogenous and exogenous origin) were identified as significantly changing in abundance with participant age (p < 0.1). The potential origins of these dysregulations are discussed. Multiple linear regression (MLR) analysis was employed to model age based on these significant volatiles as independent variables, along with gender. Our analysis shows that skin volatiles show a strong predictive ability for age (explained variance of 68%), stronger than other biochemical measures collected in this study (skin surface pH, water content) which are understood to vary with chronological age. Overall, this work provides new insights into the impact of aging on the skin volatile profiles which comprises both endogenously and exogenously derived volatile compounds. It goes toward demonstrating the biological significance of skin volatiles and will help pave the way for more rigorous consideration of the healthy "baseline" skin volatile profile in volatilomics-based health diagnostics development going forward.


Assuntos
Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Humanos , Análise Multivariada , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
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